SMTP error 554

[rinzes]

I have Webmail 0.9.5 installed. I am using the following smtp config:

$rcmail_config['smtp_server'] = 'ssl://localhost';
$rcmail_config['smtp_port'] = 465;

When sending mail I keep getting SMTP error 554 however when I use sendmail no errors occur so maybe I have a mis-config in roundcube. Any help would be appreciated 

add: here is from the errors log

[20-Mar-2015 10:01:35 -0400]: SMTP Error: SMTP error: Failed to add recipient '[email protected]' in /usr/share/roundcube/program/include/rcmail.php on line 1035 (POST /roundcube/?_unlock=loading1426856745283&_lang=en?_task=mail&_action=send)
root@mail:/var/log/roundcube#

have no idea what that means

[JohnDoh]

SMTP error 554 is rely access denied I think. Try configuring Roundcube to use SMTP authentication. In the config file there are options like smtp_user and smtp_pass for that.